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Adiabatic Quantum algorithms and QC in DFS via measurement

Here I list two papers recently posted on the arxiv which I thought interesting or important.

Adiabatic quantum algorithms and quantum phase transitions in quant-ph/0608017, Ralf Schützhold, Gernot Schaller from Dresden University of Technology reveal the similarity between adiabatic quantum algorithms and quantum phase transitions. They found that the Grover algorithm was corresponding to the first order of quantum phase transitions. They found that the second or higher order transitions were much better than first order one. With this insight, they proposed a novel adiabatic quantum algorithm for the solution of 3-satisfiability (3-SAT) problems, which is much faster than the Grover algorithm, possibly even with an exponential speed-up.

Universal quantum computation in deocoherence-free subspace with neutral atoms in quant-ph/0607175, P. Xue and Y.F. Xiao from IQOQI and USTC proposed a scheme that realizing universal quantum computation between via measurement in deterministic way. They show how to implement cavity-assisted interaction between neutral atoms and coherent optical pulses. The quantum gates act on decoherence-free subspace. Therefore the dominant source of decoherence — dephasing is highly depressed. The homodyne detection of the coherent state directly measure the relative phase of the signal state, so the photon losses only decrease the fidelity but not lead to a failure of the measurement.

Yes, I know this work. They are not the first one present buckyball quantum computers. Others have discussed them: Phys. Rev. A 65, 052309 (2002), Phys. Rev. A 65, 032322. Phys. Rev. A 67, 052318 (2003).